sdk: add express sdk

packages/sdks/express/tsup.config.ts

@@ -0,0 +1,9 @@
+import { defineConfig } from 'tsup';
+
+import config from '@openpanel/tsconfig/tsup.config.json' assert { type: 'json' };
+
+export default defineConfig({
+  ...(config as any),
+  entry: ['index.ts', 'cdn.ts'],
+  format: ['cjs', 'esm', 'iife'],
+});